... Would I have bought a NU4-6000? Even though I said I might, a few messages back, a year ago I was more in the market for two separate amps for two different rooms. For just one system needing biamping, of course either would work. I would want to find out if the NU4-6000 can go fanless like the NU3000 could.

mr. doom, I remember seeing that post when I first got the amp. Also saw a video of a guy doing it too. I'm pretty sure removing the fan/changing the fan would void warranty. Maybe after my warranty is up ill mod the fan.

Soldermizer, Sorry I forgot we talked about that already. Like i said I'd go with the NU4-6000 only if it had DSP and I had a lot of speakers to power. Else I'd stick to two units for more flexibility.

Good point abcdmku. As for needing high power, I think the NU3000 is (are) great for that. Much ado is made of continuous RMS watts but ... peak power maybe is the more important. In my case, one NU3000 driving (per channel) 2x Bose 901 II (=4 ohm load nominal) will peak (0 dB) easily on fairly loud music. This is not surprising since I have about 30 dB of boost at lowest frequencies and also a dBX expander. It is "far out man" as Chong would say, to have a fanless box that can put out 1500 watts (albeit briefly)...the trick is how loud can I play it before it goes into thermal protection.

History made! I spent money on something for the cat that the cat actually uses! Since cats like warm things I have tried a couple methods to move my "desk cat" to a top shelf so I shall have more desk top space. Now I have my two NU3000 amps (fanless, so the tops get nice and warm), side by side on a top shelf. I bought a "paver" stone (about 20x20x1 inches, about $7) that now tops both amps. This serves of course as a heat sink. Top it with a towel and install cat. Cat now happy. Next project: how to keep cat from walking on keyboard KIU&XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XX

Cats are enjoying outside time right now. Besides, just got home and the masonary needs to warm up

Here is a photo. As you can see, a rodent is subbing for a cat. I doubt the cat would cause over-heat, however, the towel could restrict airflow if draped over the edges. The whole idea of this exercise was to allow the amp's waste heat to heat the concrete paver (approx. 20x20x2 inches).

I was listening to some "trance" music and got a thermal even at not apparently too loud volume. This is not the first time, and not unusual (although it was on the amp that I "experimented upon" and I sometimes worry that my half-assed resoldering is failing.)

I just got an incredibly simple evil idea worthy of the Grinch when he figures out his reindeer substitute
What if I put the fan back in the amp, and had a switch for it? If I need to blast music, I have the fan running. If I need quiet, turn off the fan. Experience has shown that the thermal protection works ok. Best of both worlds?

Well, I have managed to kill one of my NU3000. As noted else where, one of my experiments was removing the output inductors and capacitors. That did not work (amp remained in protect). I put them back ... not very skillfully and ... amazingly the amp worked. At least until after the recent "heated cat perch" experiment. I am pretty sure the problem is one inductor (it is visibly loose). I can't seem to make a good solder bond with my limited skills and equipment. I will leave it DOA, for a project later or perhaps sell it as broken (I do that some). Anyway, it is an excuse to BUY MORE ELECTRONIC GADGETS!!! Meanwhile, the cat perch must make do with only 1/2 the heat generated.

I thought my eyes deceived me. On Ebay right now, the cheapest NU6000 is: $398. Cheapest NU3000 is: $299. I think the NU3000's have gone up some, the NU6000 is no longer twice the cost (was it ever?) I think it is time to buy a NU6000 and hope my "fan-ectomy" will work!

There is a NU3000DSP (customer return) for $299, same price as a regular NU3000. I was tempted, but I am going for power this time.

Last edited by Soldermizer; 20th February 2013 at 04:11 PM.
Reason: recount my experiences as an EBay *****